Taylor & Francis Group
Browse
taje_a_1661286_sm3345.pdf (126.55 kB)

Coal seam development characteristics and distribution predictions in marginal sea basins: Oligocene Yacheng Formation coal measures, Qiongdongnan Basin, northern region of the South China Sea

Download (126.55 kB)
journal contribution
posted on 2019-09-30, 05:10 authored by D-D. Wang, G-Q. Dong, G-C. Zhang, Z-X. Li, Q. Mao, G-Z. Song

Coal measures located in marginal sea basins are important hydrocarbon source rocks. For the purpose of effectively guiding future oil and gas exploration, the characteristics and distribution patterns of coal seams in coal measures of a marginal sea basin are systematically outlined. Coal measures in marginal sea basins can have large thicknesses, but the individual coal seams can be very thin and lack lateral continuity. In the study area, the organic micro-components of the coal are dominated by vitrinite, with very low amounts of inertinite and liptinite. The amount of inorganic microscopic components is large, but with limited drilling results, few cores and thin coal seams, which are easily overlooked during logging activities, a comprehensive analysis of the logging data may improve efficiency in coal-seam identification and thickness determination. The development and distribution of coal seams in marginal sea basins are controlled by various factors, including (1) paleoclimatic and paleobotanic conditions, which could fundamentally limit coal formation, (2) coal-forming sedimentary environmental conditions that may limit the scope of coal-seam development from a macroscopic perspective, and (3) paleotectonic and paleotopographic conditions that define the coal-forming structures. Therefore, the descending and rising cycles of base-levels, along with changes in the growth rates of the accommodation spaces, can be used to determine the horizons that are potentially favourable for coal formation and can also indicate the migration trends of coal-forming environments on the structural plane. Seismic wave impedance inversion methods could be utilised for semi-quantitative assistance for prediction of coal seams. In summary, for models of coal-seam development in marginal sea basins, the grades should be divided according to reliability, and the different reliability levels should be predicted separately.

The characteristics of coal seams developed in marginal sea basins are described.

The macerals of coals developed in marginal sea basins have been ascertained.

A development model and distribution prediction method for coal seams are assessed according to the control factors.

A model for the prediction of coal-seam distribution is presented.

The characteristics of coal seams developed in marginal sea basins are described.

The macerals of coals developed in marginal sea basins have been ascertained.

A development model and distribution prediction method for coal seams are assessed according to the control factors.

A model for the prediction of coal-seam distribution is presented.

Funding

This study was financially supported by the Major National Science and Technology Projects [2016ZX05026007-004], SDUST Research Found [2018TDJH101], the National Natural Science Foundation of China [41872172], the Natural Science Foundation of Shandong Province [ZR2019MD021] and the open fund project of Key Laboratory of Resource Exploration Research of Hebei Province.

History